https://phys.org/news/2018-07-nanoscale-biomolecule-liquid.html > To understand the intricacies of folding, scientists need to study the detailed arrangement of chains of amino acids that are shorter and simpler than proteins—called peptides—and how they fold, assemble and rotate to create a variety of shapes, or conformations. Biologists prefer to examine proteins and peptides immersed in water because that environment closely approximates the conditions inside living cells. > Previously established techniques for determining the conformation of proteins, such as infrared spectroscopy, lack the fine spatial resolution to study the tiny and diverse assemblies of properly folded and misfolded proteins. In addition, these techniques don't work well in an aqueous environment because water strongly absorbs infrared light, confounding the analysis. Water had also posed severe challenges for a pioneering technique, known as photo-thermal induced resonance (PTIR), that recently enabled researchers to examine peptide structure and conformation in air with nanoscale resolution.